Electron transfer sensitization of triarylsulfonium salts for radical curing has been known and practiced in the art (see Pappas, S. P., Prog. Org. Coatings 1985, 13, 35; Crivello, J. V. Polym. Eng. Sci. 1983, 23, 953; Kondo, S.; Muramatsu, M.; Tsuda, K. J. Macromol. Sci. Chem. 1983, 19, 999; Pappas, S. P. Radiat. Phys. Chem. 1985, 25, 633; Hagemann, H. J. Prog. Org. Coat. 1985, 13, 123; Crivello, J. V. Adv. Polym. Sci. 1984, 62, 1; Baumann, H.; Timpe, H.-J.; Bottcher, H. Z. Chem. 1983, 23, 394; Timpe, H.-J.; Bah, A. Makromol. Chem. Rapid Commun. 1987, 8, 353). A three component photoinitiator system comprised of an electron donor, sensitizer, and electron accepting initiator has been taught in U.S. Pat. No. 4,735,632.
Photosensitive tethered donor-acceptor compounds have been described in the art as model systems for the study of electron transfer (Closs, G. L.; Miller, J. R. Science 1988, 240, 440; Oevering, H.; Paddon-Row, M. N.; Heppener, M.; Oliver, A. M.; Cotsaris, E.; Verhoeven, J. W.; Hush, N. S. J. Am. Chem. Soc. 1987,109, 3258). Tethered alkyldiarylsulfonium salts useful in photocuring of cationically polymerizable monomers are known (see U.S. Pat. Nos. 4,250,053, and 4,069,054). The greater stability of triarylsulfonium salts over sulfonium salts with one or more alkyl groups attached directly to sulfur is known (see Crivello, J. V.; Lam, J. H. W. J. Polym. Sci.: Polymer Chemistry Ed. 1980, 18, 2677; Saeva, F. D. Tetrahedron 1986, 42, 6123).
A method for preparation of alkoxy/aryloxy substituted triarylsulfonium salts using alcohols and fluoro-substituted sulfonium salts has been described (see Japanese Patent 61-212555); however, no mention was made regarding reaction with primary or secondary amines.